py23 import in all nontrivial source files and unused import cleanup
diff --git a/Lib/fontTools/misc/arrayTools.py b/Lib/fontTools/misc/arrayTools.py
index 2a3c225..dad9e85 100644
--- a/Lib/fontTools/misc/arrayTools.py
+++ b/Lib/fontTools/misc/arrayTools.py
@@ -5,6 +5,7 @@
 
 
 import math
+from .py23 import *
 
 def calcBounds(array):
     """Return the bounding rectangle of a 2D points array as a tuple: